CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	May 31, 2017	May 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (908,561)	$ (1,499,787)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	219,219	232,422
Change in provision for allowance for doubtful accounts	41,724	(9,063)
Inventory reserve	(16,505)	27,150
Stock option expense	21,727	15,153
Decrease in deferred rent liability	8,070	(28,073)
Decrease in deferred tax assets		703,000
Changes in assets and liabilities:
Accounts receivable	(132,261)	151,159
Inventories	150,475	137,131
Prepaid expenses and other	(82,179)	50,774
Other assets	(39,336)	1,185
Accounts payable and accrued expenses	10,445	(30,581)
Accrued compensation	4,324	40,748
Net cash used in operating activities	(722,858)	(208,782)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of property and equipment	(96,085)	(91,556)
Purchases of intangible assets		(3,636)
Net cash used in investing activities	(96,085)	(95,192)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from sale of common stock, net		995,978
Proceeds from exercise of stock options	157,728	109,936
Net cash provided by financing activities	157,728	1,105,914
Effect of exchange rate changes on cash	(2,248)	(1,322)
Net (decrease) increase in cash and cash equivalents	(663,463)	800,618
CASH AND CASH EQUIVALENTS, beginning of year	1,888,925	1,088,307
CASH AND CASH EQUIVALENTS, end of year	1,225,462	1,888,925
Cash paid during the period for:
Interest	282	167
Income taxes	$ 800	$ 800